drivers/serial: use nr_irqs

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/drivers/serial/serial_lh7a40x.c b/drivers/serial/serial_lh7a40x.c
index cb49a5a..61dc8b3 100644
--- a/drivers/serial/serial_lh7a40x.c
+++ b/drivers/serial/serial_lh7a40x.c
@@ -460,7 +460,7 @@
 
 	if (ser->type != PORT_UNKNOWN && ser->type != PORT_LH7A40X)
 		ret = -EINVAL;
-	if (ser->irq < 0 || ser->irq >= NR_IRQS)
+	if (ser->irq < 0 || ser->irq >= nr_irqs)
 		ret = -EINVAL;
 	if (ser->baud_base < 9600) /* *** FIXME: is this true? */
 		ret = -EINVAL;